Soft-meat fruit having skins and stones or seeds within cores of the meat are frequently made into purees and sauces. Apples are a typical soft-meat fruit, and applesauce is a preferred form of product made from apples. Applesauce is conventionally made by first peeling the apples to remove the skins and then coring to remove seeds by removing the core. Large pieces of apple meat are formed. These large pieces are reduced in size by chopping or cutting into smaller pieces. Next, the reduced-size pieces of the apple meat are cooked in a long cooking apparatus, perhaps 50-60 feet long, where the small pieces are raised to a temperature of about 200.degree. F. by mixing live steam directly with the pieces of meat in the cooking apparatus.
The peeling and coring machines heretofore used frequently miscut the apples due to faulty machines or misaligning of the apples within the machines. This results in pieces of core still containing seeds and pieces of skin finding their way into the cooking apparatus. By the time the small pieces have been cooked at a temperature of 200.degree. F. and moved through the cooking apparatus, they are in a finely comminuted, soft, low-viscosity liquid condition. The low-viscosity liquid condition results in part from the mixing of water in the form of steam directly with the meat pieces. Also, the low viscosity results from the fact that in the peeling of the apples, the meat adjacent the skin, which contains the largest amounts of pectin, is removed. Pectin is a known viscosity increaser in sauces.
The low-viscosity liquid and remaining undesirable pieces of peel and seeds are then passed through a finely perforated drum, called a "finishing drum," which allows the low-viscosity sauce to pass, but traps the seeds and skin particles. The sauce resulting from these conventional processes is of the consistency of strained baby food. It is of low viscosity and has a "mouth feel" or texture free of any sized particles.
Since the peeling and coring operation leaves relatively large pieces of meat of the fruit, these pieces must be reduced in size before they can be effectively heated thoroughly throughout. Enzymatic reactions, which cause the familiar browning of cut apples, take place within a relatively few seconds after the skin has been perforated. To prevent browning of the apple pieces in the conventional process, direct steam is injected into the apple product over a long period of time. This will inactivate the enzyme which causes browning; however, as previously mentioned, the net result is the addition of large amounts of water and a subsequent decrease in product viscosity. In addition, the open steam injection process tends to steam strip out the volatile flavor and aroma components, resulting in an inferior product. Both the decrease in viscosity and the loss of flavor and aroma components are undesirable traits for applesauce.
Other attempts have been made to "blanch" the peeled and cored meat of the fruit immediately after peeling and coring. In a "blanching" process, the apple pieces are relatively large with minimum surface area and minimum perforations to reduce enzyme-caused brown discoloration. These attempts, however, have not been successful since the pieces of fruit entering the blanching apparatus are of a size too large to get rapid enough and thorough enough heat penetration into the fruit pieces to inactivate the enzyme which causes browning. When these inadequately heat-treated large pieces are converted into smaller pieces during the saucing process, the product begins to brown in a relatively few seconds.
The sauce is treated with a sweetener or flavoring agent, is heated to a pasteurization temperature to kill bacteria, and is finally fed to a filling machine for bottling or canning the sauce.